Vogue editor and Conde Nast artistic director Anna Wintour posted her first message on Twitter Wednesday, weighing in on the Supreme Court ruling against the Defense of Marriage Act. But she didn’t start her own account — Ms. Wintour sent the message through Vogue’s Twitter handle, including her initials at the end to indicate that the tweet came from her.

Today’s rulings are a big step forward for all Americans striving to achieve equality. I couldn’t be happier or more proud. A.W.